"P" on signal masts (CSX)

[Anonymous]

While visting Florida earlier this month I noticed the letter "P" affixed to signal masts. What is the meaning of the P?

[tree68]

From the site http://www.gatewaynmra.org/detection3.htm

Real railroads have two types of stop indications: absolute and permissive. Trains must stop at an absolute stop indication, but may cautiously proceed past a permissive stop. Permissive block signals are always marked, typically with a number plate, the letter "P" (permissive), or the letter "G" (grade). MoPac put a number plate on all signals, and marked the absolute ones with an "A" (just to be different most likely). Interlocking signals are always absolute. Since most interlocking signals have multiple heads, they are easily identified. Like the real railroads, if you ever need a single-headed interlocking signal, make sure to mark it "A" so there is no question it is absolute.

[Anonymous]

On the old B&O, an intermediate signal would be a Grade Signal when located on an upgrade where a train stopping might not get started again. Our "Restricted Proceed" signals of today once required a complete stop before proceeding [Stop and Proceed"]

[Anonymous]

I think someone should post Their best recolection of what every letter means... because there are quite a few..

[espeefoamer]

Check a copy of any railroad rule book. All signal aspects and markings will be described.

[kenneo]

QUOTE: Originally posted by tree68

From the site http://www.gatewaynmra.org/detection3.htm

Real railroads have two types of stop indications: absolute and permissive. ...... Like the real railroads, if you ever need a single-headed interlocking signal, make sure to mark it "A" so there is no question it is absolute.

Just to get your juices going, there is also A-PB "Absolute-Permissive Block". Very restricted in its use. It was designed to permit (usually) two different railroads to use the same streach of track without either railroad having exclusive dispatching rights. Confused? There were several pages of rules, but to make things (hopefully) simple, it would permit one train to follow another through the A-PB limits byt prohibit an opposing train from entering the A-PB limits until the train comming through had cleared the system. Esentially, an automatic interlocking of sorts.

AND, if you use a single head A signal, you MUST preceed it with a "D" signal. "D" is for Distant. A D Signal IS NOT a block signal. It will never display anything more permissive that solid yellow. It is slaved to the interlocking signal and will display red if a train is in its circuit. EXCEPT when your A Block is within a CTC system. There, it is like any other A Block. Stop Absolutely; Absolutely Stop. Controlled by the dispatcher or the interlocking operator.

Above are designed to be general statements and not tecnically accurate in all posible varients.

[Anonymous]

Uh, are you guys sure that the P doesn't stand for "post" as in, this signal is standing on a post - this particular part, where this letter "P" is affixed is the post.

Nah, maybe not. As noted above, you have absolute signals that often have an "A" on them - do not pass these - ever - (also do not pass go, do not collect $200); and then you have permissive signals that you can pass at restricted speed. P = Permissive. You may also see some that have a "G" (for "Grade")which someone also mentioned above. Its a special kind of permissive, when you're on a upgrade that could cause you to stall - again you can pass at resticted speed. You'll also see some that have "D" affixed. This will usually be on the lower of two signal heads that are on the same post. The D = Distant, and is telling you, in advance, what the next signal is going to say. i.e. the lower head is the "distant" signal and is telegraphing to you what you will see a mile or so up the track when you get to the next signal. Kinda like ESP for locomotive engineers.

[dehusman]

Actually the Mop put a number plate on the intermediates and NO number on the absolutes. The most restrictive indication a signal with a number plate could display is stop and proceed, those without a number plate could display stop.

Dave H.

[Anonymous]

Well the true answer to this question is -----p------= (proceed) , "restricted proceed " and it is a intermediate signal or also known as a permissive signal.
P = Proceed
C = stop and check
App = Approach
G = grade
S = stop and open switch
825.5 a # is the mile post at that location.
these are all intermediate signals and you do not need to stop at the (P) indication signal as it is a restricted proceed (15 mph).
per CSX signal aspect and indication rule book.
I should know being a conductor for CSX.
[8)]

[dharmon]

I guess it's a good thing that dogs don't read.......[:D]

[yellowducky]

Maybe dogs don't read, but that doesn't mean they can't. They probably are smart enough not to put in their 2 barks worth, then again, they do bark at everything.

[kenneo]

ChrisNoren --
First, welsome to the Forum. I see that this is your first post.

Since the thred was CSX specific, you go to the head of the class.

Just want to make clear a slightly off thred point --- the letters applied to signals is usually railroad specific as illustrated by the practice of the MP not putting numbers plates on its absolute signals and the SP, while not putting number plates on its absolute signals, also applied the letter "A" in a triangle. I do not know of any railroad that put number plates on its absolute signals, and as you stated, any signal with a number plate became a permissive signal. Stop and Proceed if no other instruction printed in the Special Instructions applies.

How does the CSX apply the situation where a signal (fixed or block) is not displayed properly --- specifically when a number plate should be displayed and it is missing?

[Anonymous]

Do I assume the lighted portion of the signal is always RED for A and P? -- being in CSX territory with FCRR next to my fence.

[CShaveRR]

No, of course not...if a signal with an "A" were always red, you might as well tear up the railroad beyond that point!

These letters, however, have meaning when only the signal is all red. Any other color(s), follow the signal indication.

[dharmon]

QUOTE: Originally posted by markdgls

Do I assume the lighted portion of the signal is always RED for A and P? -- being in CSX territory with FCRR next to my fence.

No because A and P is a grocery store. It's only red if your wife wants you to stop for milk on the way home, otherwise it's green meaning proceed home at normal speed.

[vsmith]

"P" on the signal mast?

Well, if there's no porta-potty around....



OK OK ya'll can stop booing now...

[Anonymous]

Yeah P on signal posts is pretty low..

..save it until you get home, man.

[Anonymous]

Well kenneo ,
First thing number plates do not need to be displayed on the signals , that is why we have mile post markers, those are very important.
If any thing is missing like a advance warning sign or a temporary speed restriction we still have to follow our train orders that we received before the trip , in return we contact the train dispatcher and his instructions are applied .
A intermediate signal that is red = You do NOT need to stop![:D]
You just proceed @ 15 mph
(Do not forget about the crossings you are blocking , people are in a hurry these days and they will let you know !...lol )
And don't forget if you "run through" a red signal that is a positive signal , get your grip (bag) your going home ! [:0]
This is why everyone one that is a conductor or engineer has to be qualified on that certain piece of track. You MUST know were you are or you do NOT go!
Signals do have safe guard systems if they fail we go to the DTC system Direct Traffic Control unlike the TCS Traffic Control System we were doing.
Also if a signal is dark (burnt out) stop @ an absolute signal
A intermediate signal you can proceed @ restricted speed w/o stopping .
The signals have a lot of different meanings (aspects) that you must know , the will warn you , way ahead of time to speed up or slow down.
Kenneo those were some great questions. I did not thing anyone that was not working for the RR would even have a clue to that info. Good job ![:D]